The present application claims priority upon Japanese Patent Application No. 2001-174044 filed on Jun. 8, 2001, which is herein incorporated by reference.
1. Field of the Invention
The present invention relates to a roll-paper printing system conducting printing on a roll paper, a method for managing a remaining amount of roll paper, a recording medium, and a roll paper with a memory. Particularly, the present invention relates to such as a roll-paper printing system which is capable of managing an amount of roll paper.
2. Description of the Related Art
A roll paper is made by winding, for a plurality of times, a continuous long printing paper to a surface of a core. In a printing system using a roll paper, printing is carried out by successively feeding the roll paper to a printing position in accordance with generation of a print image. When printing of 1 page is finished, the printed roll paper is fed a predetermined amount, is subjected to cutting or the like at a predetermined position, and then is discharged
In a case where a printing system uses a cut sheet, an image for 1 page (or an image for a predetermined number of bands) is generated in accordance with the size of the cut paper, and the cut paper is supplied per unit of paper. Accordingly, in normal cases, a paper-out condition will not occur during printing of a certain page. In contrast, in a case where a printing system uses a roll paper, continuous long printing paper is supplied by predetermined amounts, and there is a possibility in that the size (particularly the size in the length direction) of a print image may respectively differ for each printing job. Thus, there is a possibility in that a shortage in a remaining amount of roll paper will occur, and printing will be interrupted.
Thus, there have been conventionally proposed various techniques to detect the remaining amount of roll paper. For example, in Japanese Patent Application Laid-open Publication No. 60-87158, Japanese Patent Application Laid-open Publication No. 63-154567, or the like, a remaining amount of roll paper is detected by detecting the rotation of the roll paper with a rotary encoder. Other than these, there are known methods such as a method wherein an extendable-and-retractable rod is pressed to the front surface or the back surface of a roll paper and a remaining amount of roll paper is detected by the amount of movement of the rod (such as Japanese Patent Application Laid-open Publication No. 9-124184), a method of detecting a remaining amount of roll paper by optically detecting a mark provided on a non-print region of the roll paper with a sensor (Japanese Patent Application Laid-open Publication No. 10-226144), a method of detecting a remaining amount of roll paper by determining the amount of roll paper used by adding up the number of print columns.
Further, as a conventional technique relating to management of a remaining amount of roll paper, there is known, for example, a technique in which a remaining amount of each roll paper is respectively stored to a memory of a printer, and the remaining amount of roll paper within the memory is updated according to the amount of roll paper used, as described in Japanese Patent Application Laid-open Publication No. 10-25046.
In contrast to a cut sheet, it is not possible to appropriately supplement printing paper in the case of a roll paper. In a case where a printing system uses a cut sheet, the information regarding xe2x80x9cremaining amount of paperxe2x80x9d is an attribute of a paper-supplying cassette. However, in the case of a roll paper, since this is a continuous long printing paper, the information regarding a remaining amount of paper becomes attribute information for the roll paper. Therefore, as with the conventional technique described in Japanese Patent Application Laid-open Publication No. 10-25046, in the case of managing the remaining amount of each roll paper on the printer side, it will only be possible to use the roll paper with the printer to which the remaining amount is stored. That is, there is a problem in that a roll paper having been partially used cannot be used with another printer.
Further, apart from a case in which one roll of roll paper is used up upon one continuous printing, usually, a roll paper is partially used for a plurality of times of printing. Thus, in order to manage the remaining amount of roll paper, it is necessary to use a storage device which is capable of holding data until the next time of printing, and in which the data is erasable. As for such a storage device, it is possible to name, for example, a memory such as an EEPROM (Electrically Erasable Programmable ROM). In case of a memory such as an EEPROM, since the number of erasable times is as few as approximately ten thousand times, there is fear in that the memory will become unusable before the roll paper is used up, if, for example, the remaining amount thereof is minutely updated per every printing pass or per every raster. If a memory having a large number of erasable times is adopted, the cost of the memory-attached roll paper will increase. Further, if the remaining amount is minutely updated per every printing pass (every time the paper is fed), there is fear in that the load of a computer for the printer will increase and the processing speed will drop, as memory contents is frequently erased.
Thus, there may be considered a method of updating the remaining amount per a plurality of passes, and not updating the remaining amount per every printing pass. However, if updating is carried out by detecting a remaining amount of roll paper during printing, such an updating will often be useless. This is because the remaining amount detected during printing is a value obtained before a final remaining amount of roll paper is determined.
The present invention has been contrived in view of the above-mentioned problems, and an object thereof is to provide a roll-paper printing system capable of appropriately managing a remaining amount of roll paper. Another object of the present invention is to provide a roll-paper printing system capable of efficiently managing an amount of a roll paper by updating amount information, regarding an amount of a roll paper, at an appropriate timing. Further, another object of the present invention is to provide a roll-paper printing system capable of efficiently managing a remaining amount of roll paper by updating a remaining amount of roll paper at an appropriate timing.
A main roll-paper printing system for solving the above-mentioned problems comprises: carry-amount detecting means for detecting a carried amount of said roll paper; recording means for recording amount information regarding an amount of said roll paper; and updating means which makes said amount information be recorded on said recording means based on the carried amount detected by said carry-amount detecting means, said updating means making said amount information be recorded on said recording means when a physical process for indicating a break in roll-paper usage is conducted to said roll paper. Further, in another main roll-paper printing system, the remaining-amount recording means is provided on the roll paper; and the carry-amount detecting means which detects a carried amount of the roll paper, the remaining-amount detecting means which detects a remaining amount of roll paper based on the detected carried amount of roll paper and an initial remaining amount of the roll paper, and the remaining-amount updating means which makes the remaining amount of roll paper detected by the remaining-amount detecting means be recorded on the remaining-amount recording means are provided on the machine (the printer).
Features and objects of the present invention other than the above will become clear by reading the description of the present specification with reference to the accompanying drawings.